A new device called Halo Sport promises to improve performance by stimulating your mind. We zapped our brains in the name of science to see if it could really make us faster.

We’ve known for a while that the final frontier of sports performance is the mind. While athletes have been practicing different forms of meditation and visualization for years, a new device called Halo Sport, released this week, hopes to bring mental training into the 21st century. The gadget, which looks like a pair of bulky Skullcandy headphones, transmits 1-2.2 milliamps of electricity via three electrodes in order to stimulate the brain’s primary motor cortex, which controls movement.

The Halo Sport uses transcranial direct-current stimulation (tDCS), which has been used effectively in clinical settings to improve memory, learning, and intelligence and to treat depression, chronic pain, and schizophrenia. Halo calls its version of the tech neuropriming. The company is the first to offer it commercially to athletes.

According to Nick Davis, a senior lecturer in psychology at Manchester Metropolitan University who has extensively studied tDCS, most research on the topic has been conducted in a laboratory, on subjects who are given small tasks like quickly pressing a button on a computer. In these controlled settings, stimulating the brain via tDCS had quantifiable positive effects on the behavior and brain of those suffering from neurological problems like depression and Parkinson’s disease. “What we don't know, however, is whether you get the same results in the sports field, where it's a much less controlled environment,” says Davis.

Halo users are supposed to put the device on for twenty minutes before training sessions. Doing so will “put the brain’s motor cortex in a temporary state of hyper learning that lasts for an hour,” according to Halo’s website. “During this time, feeding your brain quality athletic training repetitions results in this information being more fully incorporated into your brain.”

Transcranial direct-current stimulation has been used in clinical settings to improve memory, learning, and intelligence and to treat depression, chronic pain, and schizophrenia.

There's very little peer-reviewed research on the efficacy of tDCS for performance outside of a controlled lab. However, Halo has conducted in-house studies, and their results are intriguing: it found that CrossFit athletes who used their headphones for two weeks showed a five percent increase in lower body strength. And Halo does have an impressive roster: it was founded by neuroscientist Daniel Chao and engineer Brett Wingeier, who spent more than a decade designing an FDA-approved neurostimulation device for epilepsy patients. The device is now being used by Olympic track athletes, NFL players, and members of the U.S. Ski Team, all of whom have noted promising results.

We wanted to test it for ourselves. The two of us used the headphones—which pair with an iPhone app via Bluetooth—twenty minutes before our midday lunch runs, two to three times a week. We were not testing these headphones by analyzing a specific metric—speed, strength, time, etc.—and instead were keeping an open mind, concentrating more on how it made us feel before, during, and after using them.

The sensation of being zapped by a small amount of electricity, which is transmitted into your head through half-inch rubber fingers inside the headphones, left us with varying sensations: one felt nothing, the other said it seemed like he was being tickled underneath his skull.

This is normal, says Wingeier. “It’s always interesting to hear about the way people perceive the stimulation,” he says. “Everyone seems to process the sensation differently. Some people don’t think the device is on, others feel tingling on their scalp.”

A pair of Halo Sport headphones. (Photo: Courtesy of Halo)

After the 20 minute session, we noticed varying effects: sometimes we were left with a headache that lasted as long as 30 minutes. Other times, we had a nervous energy, almost like we had just slammed two espressos. Other times we felt nothing.

Just as caffeine can be a performance booster, our tester who felt energetic after using the Halo headphones unsurprisingly reported the same effect: more energy, more enthusiasm, and faster splits—it shaved five minutes off a seven-mile run, to be specific.

The goal of Halo, however, is to improve athletic efficiency and performance over an extended period of time—not just improve energy levels on a workout-by-workout basis. “What happens when you turn on a brain stimulator like Halo is that an electric current passes across your head,” says Davis. “For reasons we don't really understand, brain cells that are near the positive electrode become a bit more active, and when a brain area is more active, it tends to be more plastic. This is called neuroplasticity, and it relates to the ability to learn things; there is evidence that simple motor actions are learned more readily when they're done with positive stimulation.”

Did we see any long term benefits after using the headphones? If we did, it’s hard to say. We used Halo during a period of intense training, where any number of other factors—diet, sleep, endocrine imbalance—could have contributed to how we felt. In other words, we weren’t able to perfectly control for the effects of tDCS, and it’s likely that not many athletes who are using this product will.

The bottom line: Halo is designed for top-tier athletes looking to squeeze that little bit extra from their potential. At $699, it’s aimed at elites, those with cash to burn, and early adopters intrigued by the possibility of getting more from your mind, in addition to your muscles, before a workout. As for us, we'll continue to use them before our midday runs, looking for any long term improvement to our strength or speed. Outside can be a pretty competitive office environment, and we'll keep training our brains while everyone else is just focusing on mileage.

“We’ve always felt it in our gut, I think,” says Brett Wingeier. “But now everybody involved in serious athletic training is realizing how crucial the brain is for performance.”

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